p-phenylenediamines containing n-alkylacetamido ethyl substituent



Patented May 8, 1951 UNITED STATES PATENT 2,552,242 OFFICE 11 PHENYLENEDIAMINES CONTAINING N-ALKYLACETAMIDO ETHYL SUB- STITUENT No Drawing. Original application March 6, 1948, Serial No. 13,525. Divided and this application March 18, 1949, Serial No. 82,283

'7 Claims. 1

' This invention relates to photographic developers and more particularly to photographic developers containing an N-alkyl acetamido ethyl substituent.

This application is a division of our application Serial No. 13,525, filed March 6, 1948.

It is known that photographic developers of the p-phenylenediamine type are valuable compounds for producing fine grain black and white photographic images and also that these compounds, especially when they contain alkyl substituents on one of the nitrogen atoms, are useful as developers in producing colored photographic images. A serious disadvantage of the p-phenylenediamine developers is that they are highly allergenic, that is, they are poisonous to the human skin and are therefore somewhat dangerous to use.

The allergenic properties of the p-phenylenediamine developers may be overcome by substituting a sulfonamide group or an amino sulfonyl group in the alkyl group on the nitrogen atom of p-phenylenediamine as described in Weissberger U. S. Patent 2,193,015, granted March 12, 1940. The substituted p-phenylenediamine developing agents are, however, sometimes too low in developing strength (reduction potential) so that it is difficult to obtain, with them, dye images of sufii'ciently high density and contrast.

It is therefore an object of the present invention to provide a new class of photographic developing agents of the p-phenylenediamine type. A further object is to provide developing agents of the p-phenylenediamine type which produce dye images having the desired characteristics.

These objects are accomplished by the present invention by the use as developing agents of compounds having the following general formula:

NHa

where R is a lower alkyl group such as methyl,

I (CH OOMO O HONO -r 2 ethyl, or propyl, R. is a lower alkyl group and X is hydrogen, a lower alkyl group or a lower alkoxy group.

By lower alkyl group, we mean a methyl, ethyl or propyl group. By lower alkoxy group we mean a methoxy, ethoxy or propoxy group.

Compounds of this class which may be used according to our invention are as follows:

1 C I\l /C H NHCOCH l-amino-N-ethyLN- B-acetmnidoethyl) -aniline 2 C355 CZHJNHOOCHQ I NR2 4-a1nino-N-ethyl-N- (B-acetainidoethyl) -1n-toluidine 3 CzH5 CQHQNHCOCHJ I N z el-amlno-Nethyl-N-(B-acetamidoethyl)-m-p11c11etidi11e The preparation of our developers may be summarized by the following reaction scheme which indicates the general method used in preparing Compound 1.

CHgOHgNHC 0 CH3 CHQCHZNHC OCH CHaCHaNHC O CH Zn H I I NO The specific compounds illustrated above were prepared as follows:

Compound 1, [4-amino-N-ethyl-N-( s-acetamidoethyl) -aniline], was prepared from N- ethyianiline by the following series of reactions:

(as) N-(B-amznoethyl) N ethylaniZina-A mixture of N-ethylaniline (2 moles) and B-bromoethylamine hydrobromide (1 mole) was placed in a flask in an oil bath and the temperature of the oil bath wasraised to 145-150" C. during 45 minutes. The reaction mixture was stirred at this temperature for 2 hours, cooled, diluted with water, and made alkaline with 49% sodium hydroxide solution. The amine was extracted with ether, the ether solution was washed with water and the ether was evaporated. The residue was distilled under reduced pressure. The fraction that boiled at Bil-122 at 6 mm. was collected.

(b) 4 amino-N-ethyZ-N-(p-acetamidoethyl)- aniline. N-(o-aminoathyl)-N-ethylaniline (1 mole) was added to 105 'ml. of acetic anhydride with stirring and cooling so that the temperature did not rise above 80. The solution was then heated at 100 for 30 minutes and diluted with 590 ml. of water. The mixture was acidified with 250 ml. of concentrated hydrochloride acid and stirred until solution took place. After cooling to O", the amine was nitrosated by the addition of a solution of "10 g. of sodium nitrite in 150 ml. of water during a period of 30 minutes. The solution was stirred at 0-5 for minutes then further acidified by the addition of 200 ml. of concentrated hydrochloric acid. This solution was maintained at 1015 and 135 g. of zinc dust was added in small portions during the course of 1 hour. The colorless solution was filtered to remove the excess zinc and made alkaline with 1 l. of ammonium hydroxide. The diamine was ex racted with chloroform. The chloroform solution was washed with waterand dried over anhydrous sodium sulfate. The chloroform was distilled at atmospheric pressure and the diamine was distilled under reduced pressure. The portion that boiled at 204-206 at 2 mm. was collected.

Compound 2, [-amino-N-ethyl-N-(ii-acetamidoethyl)-m-toluidinel, and Compound 3, [4- amino N ethyl-N-(,B-acetamidoethyl) -mphenetidinel, were prepared from N-ethyl-m-toluidine and N-ethyl-m-phenetidine, respectively,

4 amino N ethyl N (p-acetamidoethyl) aniline grams 1 Sodium sulfite do 2 Sodium carbonate do Potassium bromide do 2 Water to 1 liter.

Coupler (ZA-dichloro-l-naphthol) grams 2 Sodium hydroxide (10% solution) cc 20 v For use (b) is added to (a).

The developing agents described in the present application may be used to form photographic images by development of exposed silver halide contained in the usual gelatin carrier or in carriers such as collodion, water-permeable cellulose ester or water-permeable synthetic resin. Our developing agents may be used with photographic films containing the coupler in the emulsion layer as described in Mannes and Godowsky U. S. Patent 2,30%,940, granted December 15, 1942,

or Jelley and Vittum U. S. Patent 2,322,027, granted June 15, 1943. When used in this way, a developing solution similar in composition to part (a) in the alcove example is suitable.

R omc-umnoon' where R and R are lower alkyl groups and X is selected from the class consisting of hydrogen, lower alkyl groups, and lower alkoXy groups.

2. An amino compound having the formula where R, and R, are lower alkyl groups.

3. An amino compound having the formula R CHzCHzNHCOR where R and R are lower alkyl groups.

4. An amino compound having the formula where R and R are lower alkyl groups.

5. An amino compound having the formula CQI; CHiOHgNHC OCH;

6. An amino compound having the formula Oi s CH;CH,NHC OCH;

8 '7. An amino compound having the formula 02m QHzCH NHCOOE; 

1. AN AMINO COMPOUND HAVING THE FORMULA 